


Frostbite

by hearts_n_vibez



Category: Hunter X Hunter
Genre: Aged-Up Character(s), Alternate Universe - Modern Setting, Angst, Fluff, Hurt/Comfort, M/M, Other Additional Tags to Be Added
Language: English
Status: In-Progress
Published: 2019-06-15
Updated: 2019-06-15
Packaged: 2020-05-12 12:54:16
Rating: Teen And Up Audiences
Warnings: Graphic Depictions Of Violence
Chapters: 2
Words: 4,196
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/19229545
Author URL: https://archiveofourown.org/users/hearts_n_vibez/pseuds/hearts_n_vibez
Summary: Becoming sick was one thing that Killua didn't think he was capable of being, and adjusting to it was just as hard as accepting that he was.It has it's ups-and-downs, but the full-time care and attention from Gon was all he could ask for.But being ice cold wasn't really what he had in mind while in this state...and it's not something that's common either.





	1. Chapter 1

 

 

 

Killua really didn't have to worry about his health. Like  _at all_. He was basically immune to most things that easily makes anyone else (expect for him) sick, so he could handle more intense mechanics and also has a very high endurance.

 

It would seem as if everything would be a breeze, right? Well...there are some drawbacks.

 

The negative side to this was that his family used him as bait for underground missions. Those flashbacks and experiences are the only regret he has against this  _‘power’_ ; he didn't have a  _choice_. He wanted to forget all about that, and meeting Gon helped in doing just that.

 

“Gon, have you seen my chocorobots? Killua asked as he searched all throughout the kitchen. He had stocked up on his supply, but now, he couldn't find not  _one_.

 

Gon showed up beside him, an eyebrow raised and arms crossed. “Killua you ate through them all yesterday, the last 5 boxes at least.”

 

Killua froze, turning to look at Gon with wide eyes, “I did? Damn...” He mumbled as he internally punched himself. It always ended like this, Killua going on a chocolate-eating spree and not remembering until Gon reminds him the next day.

 

“Killua, you need to stop eating like that. You know you can become sick or have much more issues to deal with,” Gon said with a frown. He sounded serious, but Killua could only chuckle at it. 

 

There's no reason for it.

 

“Gon, you know I can't get sick, so saying that is useless.” Killua opted to get a popsicle to replace his appetite for chocolate, mentally making a note to buy some more. Leaning against the island that stood in the kitchen as Gon looks down at him.

 

“But you  _did_  say you had a stomach ache yesterday, so that tells us something!”

 

“It tells us that my stomach was hurting, but it doesn't necessarily mean that I'm sick.” Even after all these years they've known each other, Gon still fears about that possibility, and Killua just doesn't understand why he  _does_.

 

As he licks another stripe up the popsicle, an involuntary shiver goes down his spine, and it feels as if the temperature dropped  _dramatically_  in seconds. “Gon, did you turn the AC on?” He asks, looking back at Gon who's now sitting on the sofa.

 

Gon looks over at him, shaking his head, “No, I didn't touch the thermostat all day.”

 

“Well it just got cold all of a sudden.”

 

 _That_  makes Gon even more confused, and as well shocked. “It's 80° degrees, Killua! How are you cold?”

 

Killua shrugs, another shiver vibrating through his body. “I don't know...maybe it's this popsicle?” He looks at the treat in his hand, seeing it melt some and dripping down to his fingers, making them sticky.

 

It was... _weird_ , he'll admit it. It was a hot day, so being cold was something that one wish they  _could_  be, not  _intentionally_  be, there's a difference.

 

Quickly finishing his melted popsicle before it made a sticky mess, Killua went over to the sink to warm his hands. When he thought the water was warm, he stuck his hands in the sink and —

 

“Ow!!” He hissed as he pulled his hands back. They were burning as if on  _fire_. It actually hurt to put his cold hands under hot water, and that wasn't normal at all. Now he was really concerned and confused.

 

_What is going on?_

 

“Killua!” Gon ran over to his side, looking at him with a worried look. “Are you okay?! What happened!”

 

“Just...my hands burn is all,” Killua cringed, rubbing his hands at the aching joints. “Is the water hot to you?”

 

Gon took his finger under the running the water, “No, it's not hot at all! Not even warm, it's still cold!”

 

What? How is that even possible? It felt  _boiling hot_  just a minute ago! Hell, it even burned his hands! “Uhm...” Killua didn't know what to say, no words couldn't form a sentence that would actually make sense.

 

“Killua?”

 

He quickly zoned back into reality, and looked up at Gon. He didn't want him worrying so much, so it was better to avoid the situation at hand. He smiles softly, “Gon, do you wanna help me in shopping for groceries? We really need to stock up and cook dinner.”

 

Gon blinked at the sudden change in expression. It was few minutes in until a smile grew onto his own face, “Sure Killua! I'll go get dressed!”

 

It was when he was out of the room and the sounding of a shutting door that Killua dropped the smile and let out a sigh, examining his hands. They were tingling now, with a little red showing from irritation. Another cold chill went through his body, and did it just get colder?

 

It probably was just a phase, and Killua would grow out of it by the end of the day. Nothing to be worried about or get caught up on. He should really get dressed too, and grab something to warm his hands.

 

Since he already had on some shorts and a presentable dark-blue shirt, he went to grab his shoes that stayed near the front door, and sat on the sofa to put them on. When he was done lacing them up, he went into his room to grab the mittens he put away until winter. It was a weird combination of clothing, but better safe than sorry.

 

Killua went back out, and saw Gon waiting on the sofa with soft clothing on. He looked to him with a smile,

 

“Okay! Ready to go, Killua?” Gon said as he got up, walking to the front door. Killua shoved his hands in his pockets, sighing deeply as they both made it out of the door.

 

When a draft of wind blew across his face,it tickled his nose, and a sneeze had made its way out. It was so harsh that it had actually  _hurts_ , and it even shocked him. The only time he sneezes is when he's around a lot of dust and dirt, not from wind blowing, and did he mention his throat felt a little dry?

 

He  _hopes_  it's not what he thinks it is. All these symptoms seem too familiar to not understand, he even remembers when Gon was the same way, but that was only when he was  _sick_. His heart kicked up its tempo as he felt fear radiate through him.

 

“G-Gon, let's hurry onto the store and come back. Don't want us getting caught up in the heat,” Killua said, swiftly walking faster in front of Gon.

 

“Okay, Killua! Hey, wait, slow down!” Gon's voice shouted behind him as he sped up to catch up, but Killua could barely hear him; everything sounded muffled.

 

He was just thinking of what to make for dinner, to get his mind off of things. The hands in his pockets still tingles, and it seemed to get stronger. But once again,

 

 _There was still nothing to worry about_.

 

 

**—–•°||°•–—**

 

 

Numbness and freezing cold was all he could feel, shivering in the confinements of his 4 thick blankets. He come to find out that he hates sneezing, and coughing. Ever since they've gotten back from the store, it seemed as if ‘ _the phase’_  had gotten worse.

 

He took at least 2 hot showers and cuddled up together near the heater, but it didn't do anything to solve this problem. Pounds of used tissues near the spot where he laid, as well as cough drop wrappers. He felt like he could  _die_ , this was torture and it was the official day that he was pronounced  _sick_.

 

At least, from Gon's diagnosis, he is.

 

“Killua...” Gon peeked his head through his room door, a sad smile on his face. “I got you some more medicine, it'll help with the pain and aches...”

 

Killua groaned, a rapid thump of a headache coming on. “Come here...” his voice sounded strained and wrecked, throat dry even as he swallowed. Gon made his way to the bed, sitting on the edge while pouring the medicine into the measuring cap.

 

It tasted disgusting, but Killua knows it'll help him while in this condition. He took it once it was handed to him, gagging at the taste before giving back to Gon. “I hate it...”

 

“I know, but you have to take it if you wanna get better soon, Killua.” Gon said, putting away the medicine for the time being. “Is there anything that will make you feel better?”

 

“Hmm...chocolate...” Killua sat back on his pillow, closing his aching eyes. Chocolate was always the key to everything and anything.

 

“We didn't buy chocolate, remember? You said you didn't want any...” Gon frowned when he saw Killua groan in what he presumed pain again, rubbing his head.

 

“Well can you stay here with me?” He opened his watery eyes again, “I don't want to be left alone...” His tone sounded quiet at the end, almost in a plea and Gon felt sorry for Killua. He's sure this is the first time this ever happened to him, so he might be scared of what could happen.

 

But...

 

“Killua if I stay here with you, I could become sick too, and both of us being sick won't help at all,” He reasoned, feeling quite bad.

 

“Please...” Killua begged quietly, his eyes shined from the moisture, and the break in his voice made it sound like he was about to cry. Gon's heart couldn't take it, and so, he gave in.

 

“Okay, I'll stay here with you.” Gon got comfortable on the bed, staying a few meters apart from the bedridden. A  _very_  cold hand was placed on his arm, and it made his freeze up. He looked up to see Killua with a smirk,

 

“Good, because even if I am... _sick_ , you know I can still kick your ass, right?” He said before coughing softly into his other hand.

 

Gon chuckled, “Yeah, no. You're not moving from this bed unless you have to use the bathroom,” He winked, “So I'm going to take care of you, and you're going to follow everything I say.”

 

“Rules are for fools.”

 

“And sick is for the weak,” Gon teases, seeing Killua with a pout and it makes him chuckle. Even if he's sick, he's still the same Killua. “Trust me, Killua, I'll nurse you back to health.”

 

Killua didn't want to get treated like a baby, he can full well take care of himself, just not for the first day. Once he gets the hang of it, he doesn't need Gon to do everything for him, but...the idea of getting everything without complaints  _did_  sound pretty fun, and always remember,  _chocolate_.

 

Maybe being sick wouldn't be so bad, he just have to work out the kinks first, or at least figure out how to warm himself back up.

 

“Gon, can you get me a cup of hot chocolate?” Killua asked, before a sneeze sounded that he blew into another napkin. “And this time, make sure you use milk.”

 

Gon smiled, getting up quickly, “No problem!” He went back out, and closed the door behind him, leaving Killua to his own devices.

 

Which is sneezing, coughing, and wishing he could stop shivering. That's really the only bad side to this, and he doesn't know how anyone can get through the day dealing with this.

 

It was a few minutes later, that Gon came walking back in, holding a mug of hot chocolate in his hands. Killua looked up, and smiled, holding his hands out.

 

“Be careful, don't want you burning yourself,” Gon said as he handed him the drink gently.

 

He scoffed, “Like I don't know that already, Gon.” Just because he's sick does not mean he's weak, damn it! It just means he's not good right now. Taste testing the hot chocolate and confirming that it was indeed good, he continued drinking as it helped him with pain and also soothe his sore throat.

 

It was peaceful.

 

Gon smiled at the look of content on his face, other than the look of utter despair, and decided it was time to move onto the next part. “I'm going to take your temperature, Killua, so I'm going to need you to put the mug down.”

 

“Can it wait until after I'm done?” He said, groaning.

 

“I mean, I thought hot chocolate makes you sleepy, and I don't want you to go to sleep before I could take your temperature,” Gon got out the device, smiling softly, “So can you please put the drink down? It will only take a few seconds.”

 

He heard a few grumbles before, eventually, Killua putting the mug down on the nightstand, pouting. “I'm going to need you to open your mouth, Killua.”

 

The look of confusion crossed Killua's features, opening his mouth all the same. Gon placed the tool there, signalling Killua go close his mouth around it. They've waited, and waited, and the numbers...didn't go up. It went  _down_ , and Gon had to do a double take.

 

That never happened before. When he's sick, his temperature always shot through the roof but with Killua...it went down. He didn't have a fever but he had  _something_.

 

“Gon?” Killua's voice muffled around the device. He saw him with wide eyes and was frozen to his spot. “What is it? Is it bad?”

 

Gon seemed to come back, shaking his head, “N-No, it's just...wow.”  _Wow? What did that even mean?_

 

Gon reached for the device, and Killua released it from his mouth, “You should get some rest, Killua. You're going to need it since you're sick,” He said, chuckling.

 

“ _After_  I finished my hot chocolate,” Killua grumbled out, reaching for his drink again while eyeing Gon. He was acting  _very suspicious._

“Of course, well I gotta go check something, Killua. I'll be  _right_  back,” Gon smiled as he moved for the door and was out of the room. Killua's continuous gaze on him made him sweat, closing the door. Now he finally felt he could breathe,  _and_  figure out why Killua's body temperature was so  _low_.

 

That was anything but normal, and now, it was time to do some research.

 

 


	2. Chapter 2

**Notes for the Chapter:**

> Decided to write two chapters in one day okay, sue me.

 

 

‘ _Hypothermia..._ ’

 

Gon eyed the word that was in the suggestions. The description of having abnormal body temperature at decreasing speeds with illness was enough of an explanation.

 

Many more said a virus to the blood or an open touching of cold air for too long. Even with all he's found and red over, he hopes it's nothing near  _severe_. This was the first time Gon has ever seen Killua sick, so it must have been something to happen, especially if he's immune to basically anything.

 

Then what happened earlier that morning, it wasn't just any usual thing to happen, Killua had said that his hands burned when touching the cold water, so that's something to also search up. Clicking on the search bar, he quickly typed it in, and a bunch of results popped up for one word.

 

“Peripheral neuropathy? A condition where the hands or feet burn due to nerve damage of an underlying condition...” It sounded pretty serious, and Gon  _sincerely_  hopes that's not the case. He'll have to take Killua to a doctor if the medicine doesn't do anything...

 

“ _Gon..._ ” Killua's moaning voice called out to him from his room, causing Gon looked up from his laptop.

 

“Yeah, Killua?”

 

“Can you come here?”

 

“Alright,” Gon bookmarked the page for later, shutting down the PC and walking out of the room to Killua's. Once he got in, all he saw was a lump covered by blankets and covers, a heater blowing so intense, he felt like he started to sweat.

 

Killua peeked his head up from the covers, waving his head for Gon to come over, “I thought you would be asleep, Killua. You need rest.” Gon said, sitting on the edge of the bed beside Killua.

 

“I know but, I just can't...” Killua strained out, shivering, “I'm so c-cold...” He sniffled out before getting a tissue and blowing in it. Gon cringed, he hated seeing Killua like this.

 

“Are your hands still tingling?” Gon said, looking down at the pale, skirmish hands. Killua moved his fingers around, “No, it only happened when that cold water was running...”

 

“Can you turn the heater up for me, Gon...” Killua mumbled out quietly. He sounded very tired, and even a yawn came out of him, but he couldn't just  _sleep._

 

Gon turned to the heater, seeing the dial turned all the way up, “Killua, it's already at its MAX.” He said.

 

“Mm, I'm s-so cold,” Another shiver came, and he felt like he couldn't take it anymore.

 

He moved around a little, sitting up as best as he could with a throbbing headache, “Can you hold me?” Aching, trembling arms stretched out wide in invitation for a hug.

 

“Killua, you're sick.”

 

“Please...”

 

_Damn it, he couldn't say no, especially since Killua looks so miserable._

 

Gon engulfed him into a warm hug, making Killua sigh in content. He felt warmth while Gon could feel was freezing cold. It was like someone stuck him in a freeze for more than 24 hours, how is that even possible?

 

“Mm...warm..” Killua smiled a little, squeezing tighter on Gon, making him jump in surprise. “If you have to cough or sneeze, tap me so I can let you go, okay?” Killua nodded, just letting himself lay in the warming heat of Gon's body.

 

Gon figured since Killua is sick, that he should massage his aching muscles, fingers pressing tenderly into the flesh while still in the embrace. A smile made its way onto his face as Killua sighed once more in content; he wanted him to be as comfortable as possible, even if he felt he could melt away from the heat of the heater.

 

It had been awhile, and Killua had long gone fell asleep in Gon's arms, but Gon kept up with his massages. It was nice to see his face not distorted in pain and discomfort, it looked at if he wasn't in pain at all, and it was all he could ask for. He never wanted to see his best friend like that.

 

When he felt like it was enough, he maneuvered Killua make into bed and under the sheets, making sure he wasn't awoken by it or in discomfort, before moving out of the room.

 

Closing the door carefully, he went into the living room and over to the home phone. Instead of just making an appointment with a doctor, he'll just call up a doctor. A doctor that's a very close friend.

 

Checking the time, it read 9:00PM, so he must  _very_  still be up, and on it went to dialing the number, hearing it ring 3 times before a pick-up.

 

 

“ _Hello?_ ”

 

 

“Leorio...”

 

 

_“Hey, Gon! What is it bud? Do you need something?”_

 

 

“Can you come over? I need to talk to you...”

 

 

**—–•°||°•–—**

 

 

He arrived quite fast, as if it were an emergency. Only 10 minutes after the phone call, and Gon has to give credit. This was the fastest he's seen Leorio pull up to a place, so he deserves some well received respect.

 

They both got comfortable; Gon telling Leorio the details quietly, as to not wanting to wake Killua by any chance.

 

“So, let me get this straight...” Leorio said as he tilted his glasses back up, “Killua is now sick, and things aren't looking well with him?”

 

Gon shook his head, “No, it's like, he keeps claiming he's cold even when hot waves of heat are blowing on him, and that his hands tingling when they're under cold water.” He looks down at his own hands, as if imagining they were Killua's own. “I just don't know...”

 

“Hmm, well it sounds like Killua is very ill, and he needs full rest along with 3 hot showers a day,” Leorio stated, crossing his arms, “I don't know when the little brat got sick, but it only sounds like he has a cold fever.

 

“A cold fever?” Gon said, raising an eyebrow.

 

“Or in other words, just a common cold, with low body temperature. I'm sure this will resolve in weeks time, but you have to keep a lookout on him just incase anything else becomes or looks more serious.” Gon nodded in understanding, looking determined. He doesn't want anything to happen to Killua, especially since he's so vulnerable right now.

 

“Okay.”

 

“Good. There's nothing to be worried about, Gon. Just call me if anything else happens,” He said before standing up with a grin and putting Gon in a headlock, “This is the most I've ever seen you tense, kid! Relax some!” He dug his knuckles deep into his head, and Gon chuckled.

 

“Ah! Stop, Leorio! You could wake Killua!”

 

“In fact, I'm already awake...”

 

The two looked back to see Killua with hands on his hips, and clothes wrinkled from the amounts of tossing and turning. His hair was disheveled, and dark bags rested under his eyes, he looked depressed. “And I can't go back to sleep, so thanks a lot guys.”

 

“Wow, you look terrible.” Leorio frowned from the sight, seeing Killua roll his bloodshot eyes.

 

“Yeah, I've noticed.”

 

Gon got up, walking over to him, “You need to go back to bed, Killua. You shouldn't be walking around,” He said, pressing Killua back towards his room. Killua grabbed his hand, making him jump.

 

“Where did you go, Gon? I missed you...I was so cold without you there...” Killua says before nuzzling his head close to his chest; it was not what he expected. His hand started to feel numb from the intense amount of freezing cold on it, and he cringed.

 

“I had to make a call, and that call was Leorio. Sorry...” He answered, bringing his other hand to pat his head. He heard a whistle behind him, and Gon saw Leorio standing to the side with a smirk.

 

“I'll leave you two lovebirds to it, I've got to go get ready for work tomorrow,” He walked towards the front door, opening it before looking back, “Remember what I had said, Gon.”

 

All the while, Killua was flushing crimson at his word choice.  _Lovebirds?!_

 

He nodded, and watches as the door shut after him. Killua lifted his head up, “What did that old man tell you?” He said with squinted eyes. It reminds him of a cat getting ready to pounce on its toy. Gon chuckled,

 

“Nothing much, now let's go get you back to bed.” Gon walked him to his room, hand in hand. They both sit on the bed, and it looked as if Killua turned the heater off in advance. He must've noticed Gon sweating like crazy earlier.

 

What a blessing.

 

“Okay, Killua, you need to take your medicine again, and I know you hate it, but you need it,” Gon said as he grabbed the medicine bottle he forgotten to put up from earlier. Killua pouted, looking at the measuring cup of medicine in Gon's hands before he reluctantly grabbed it and swallowed it.

 

He shook his head quick to get rid of the bitter taste, and it turns that it wasn't such a good idea, especially since he had a headache the size of a boulder. He felt light-headed, leaning onto Gon for balance. They had a quick laugh about it, before Gon had said for Killua to take a bath, and that it should help in the aches.

 

With a roll of eyes, Killua got up and went for the bathroom that was in his room. He found out that Gon was indeed right, and stayed there for at least an hour, until the water ran cold and he jumped out. It  _burned_ like hell; Killua whined from the burning.

 

It slowly reduced to a vibrant thumping as he dried off and put on his sleeping, that was a tank top and shorts, and then called Gon back into the room. It seemed that Gon went ahead and took a bath as well, for he was in a change of clothes too.

 

They both relaxed a little bit, before they both found themselves in the position as before. Gon was rubbing his hands through Killua's hair, making him hum in favor to the touch. Though Gon knew the risk of still becoming sick, being in Killua's presence and atmosphere helped calm his nerves, for he can see if something happens. And what made it more special, was that Killua wanted him there.

 

“Gon?” Killua's voice, muffled by Gon's chest, called out to him.

 

“Yeah?”

 

“Will you…be here with me a-all night?” He asked again, gripping tightly onto the sheets. Gon saw his face flush pink, and he knew that he was embarrassed.  _So cute._

 

He chuckled, “Yes, I promise I'll be here with you, until morning and forever.”

 

Killua sighed from hearing that, and he could finally float away into the abyss of sleep. It wasn't until 10 minutes after, that Gon followed the same process.

 

 

**Notes for the Chapter:**

> More than likely will be a short fic, meaning 5 - 10 chapters (Heh, whoops) (－‸ლ), but anyway, I'll see you in the next one! (๑•ᴗ•๑)♡

**Author's Note:**

> This was something that just popped into my head, and I only wanted this to be a one-shot, but I can see this turning into an actual good fic and I want to know if you guys will like that. 
> 
> Please comment what you think, and if it's a yes, then onto writing 12 chapters it is! (I swear I love putting pressure on myself, it helps me work better XD)
> 
> But I hope you all enjoyed whatever this is, and I'll see you in the next one! (๑•ᴗ•๑)♡


End file.
